Head and neck squamous cell carcinoma is a cancer (malignancy) that arises from cells of the outer layer of skin and mucous membranes in the areas of the nose, throat, and mouth. Squamous cell carcinoma is classified by its location and can appear in the mouth (oral cavity), including the lips, tongue, underneath the tongue, the hard palate, the gums, the inside lining of the cheeks and lips, the salivary glands (rarely), the nasal cavity and paranasal sinuses, the middle area of the throat (oropharynx), the upper part of the throat (nasopharynx), the voice box (larynx), the lymph nodes of the upper neck, or the lower part of the throat (hypopharynx). Squamous cell carcinoma may also spread to other parts of the body, such as the lungs. Most squamous cells cancers occur in the upper aerodigestive tract, which includes the mouth, lips, tongue, throat, and voice box (larynx); however, squamous cell carcinomas can also occur on the skin of the head and neck. Three-quarters of nasal sinus cancers are squamous cell carcinomas.

Head and neck squamous cell carcinoma (HNSCC) may also be referred to as squamous cell carcinoma of the head and neck (SCCHN). Depending on the location, it may also be referred to as laryngeal carcinoma, nasopharyngeal carcinoma (NPC), nasal sinus carcinoma, oropharyngeal carcinoma, oral cancer, sinus cancer, or tongue cancer.

Squamous cell carcinoma of the head and neck is caused by DNA mutations (abnormalities) in cells that occur due to exposure to carcinogenic (cancer-causing) risk factors such as tobacco use (smoking, chewing tobacco, and snuff) and chronic or heavy alcohol consumption that cause the cells to grow and form a tumor in an area of the head and neck. The combination of using tobacco and drinking alcohol has the highest risk factor (75%) for developing squamous cell carcinoma of the head and neck. Additional risk factors for developing squamous cell carcinoma of the head and neck include having been infected with the human papilloma virus (HPV) through oral sex or the Epstein-Barr virus, eating Cantonese salted fish, chewing Paan (betel quid) which is popular in Southeast Asia, exposure to wood dust (logging) and smoke, exposure to asbestos, metals, textiles, ceramics, nickel dust, formaldehyde, and synthetic fibers in the workplace, eating fermented foods, exposure to radiation, poor oral hygiene, being Chinese, or more rarely, having a family history of inherited disorders that increase the risk of cancers.

Symptoms of squamous cell carcinoma of the head and neck depend on which area the cancer is located in, such as the lips and mouth, salivary glands, sinuses and nasal cavity, nasopharynx (nose and throat), or throat and larynx (voice box). Squamous cell carcinoma of the lips and mouth may appear as a lump, open sore, or area of bleeding, or a red or white patch inside the mouth, on the lip, or tongue. Additional symptoms may include earache, persistent sore throat, discomfort when chewing or swallowing, and swollen jaw. Symptoms of squamous cell carcinoma of the throat and larynx may include hoarseness, discomfort or difficulty when swallowing (dysphagia), ear, jaw, or neck pain, a neck lump or swelling, or a sense of something being stuck in the throat. The most common symptom of squamous cell carcinoma of the salivary gland is a painful lump in the cheek, on the tongue, on the roof of the mouth, or under the chin that grows slowly, or numbness or paralysis of the muscles in the face. Symptoms of squamous cell carcinoma of the nasopharynx (nasal cavity and throat) may include painless, swollen glands (lymph nodes), headaches, persistent stuffy nose, frequent nosebleeds, frequent ear infections, ringing in the ears (tinnitus), hearing loss, trouble speaking or breathing, pain when swallowing, and sore throat. Symptoms of squamous cell carcinoma of the sinuses and nasal cavity include persistent stuffy nose, pain in the upper teeth, blocked sinuses, chronic sinus infections that do not clear with antibiotics, numbness or pain in the face, forehead, or between the eyes of behind the cheeks, a bulging eye, and nosebleeds.

Treatments for squamous cell carcinoma of the head and neck depend on the location of the tumor, its size, and whether the tumor has spread (metastasized) and include surgery, chemotherapy, and radiation therapy, or a combination of both, and rehabilitation. Treatments for squamous cell carcinoma of the upper aerodigestive tract (mouth, lips, tongue, throat and voice box ) are usually radiation therapy (high-energy X-rays, protons, or other radiation) or radiation therapy combined with surgery. Chemotherapy (drugs that kill cancer cells) may also be used, depending on how advanced the cancer may be. Treatments for squamous cell carcinoma of the larynx (voice box) include radiation alone or combined with surgery that preserves the patient’s ability to speak. Chemotherapy may also be used to increase the chances of preserving the larynx. If the larynx is removed by surgery, several devices or methods, such as an electrolarynx, esophageal speech, or tracheoesophageal puncture, can be used to restore speech. Treatments for small, early-stage squamous cell carcinoma of the salivary glands can be treated with surgery. Larger tumors that have spread (metastasized) are treated with both surgery and radiation. If the tumor cannot be removed, it is treated with radiation and chemotherapy. The primary treatment for squamous cell carcinoma of the nasopharynx is high-dose radiation, followed by chemotherapy and surgery, if needed. Chemotherapy is especially effective for nasopharyngeal cancers caused by infection with the human papilloma virus (HPV). Squamous cell carcinoma of the sinuses and nasal cavity tends to be advanced by the time it is diagnosed. Since the goal is to prevent the tumor from invading the skull near the eye and brain, surgery is performed to remove as much tumor as possible, followed by radiation therapy to kill the cancer cells. For large tumors, radiation therapy may be administered before surgery to shrink the tumor. Recent research has shown that oropharyngeal cancers in patients infected with the human papilloma virus (HPV) have a better outcome (prognosis) than others and may require less treatment. Newer immunotherapy treatments, such as the PD-1 inhibitors, pembrolizumab and nivolumab, that use the body’s immune system to attack cancer cells have shown some preliminary promise in treating squamous cell carcinoma of the head and neck. Due to squamous cell carcinoma treatment-related side effects, many patients need to work with rehabilitation specialists and multi-disciplinary teams to manage dental problems, difficulty eating, thyroid concerns, hearing loss, difficulty breathing, and speech therapy.

There are several online, local, national, and international support groups for squamous cell carcinoma of the head and neck, including the following: Cancer Support Community - https://www.cancersupportcommunity.org/head-and-neck-cancer Head and Neck Cancer Alliance - https://www.headandneck.org/support-community/ Support for People with Oral and Head and Neck Cancer (SPOHNC) - https://www.spohnc.org/

The outcomes (prognosis) for squamous cell carcinoma of the head and neck depend on how far advanced the cancer may be and its location. In general, small, early-stage squamous cell carcinoma of the lips and mouth can usually be cured. Some squamous cell tumors that have spread to the lymph nodes may be curable. Larger squamous cell tumors and those that have spread (metastasized) have poorer outcomes. Small squamous cell carcinomas of the throat and larynx that has not spread can usually be cured. Early-stage squamous cell carcinoma of the salivary gland may be cured with surgery. Squamous cell carcinomas that appear under the tongue or in the minor salivary gland that have spread to the facial nerve and bulky cancers have a poor prognosis. Squamous cell carcinoma of the nasopharynx that has not spread can be cured by radiation therapy in 80% of cases. More advanced cancers that have spread have a poorer prognosis. Since squamous cell carcinoma of the sinuses and nasal cavity are more often diagnosed at an advanced stage, these often have a poor prognosis, and only 50% of these cancers on average are cured.

The most common complications of squamous cell carcinoma of the head and neck are treatment-related. Surgery for head and neck cancer can change or even disfigure a patient’s appearance and require several plastic surgeries, can alter the ability to eat, swallow, or speak, or lead to long-term facial, neck, and lymph node swelling. If the patient’s larynx is removed or other surgery is performed on the neck, permanent numbness of the neck and throat may occur. If neck lymph nodes are removed, the neck and shoulder may be still and weak. Radiation therapy for squamous cell carcinoma of the head and neck may cause irritation, redness, mouth sores, persistent dry mouth, difficulty swallowing (dysphagia), altered or lost sense of taste, nausea, earaches, skin swelling or drooping, changes in skin texture, and jaw stiffness. Treatments for cancer treatment-related side effects are an essential part of cancer care.

If you experience any of the symptoms of squamous cell carcinoma of the head and neck, such as a sore, lump, area of bleeding, white or discolored patch on the lips or in the mouth, a lump or swelling in the tongue, jaw, or neck, persistent sore throat, persistent hoarseness or difficulty swallowing (dysphagia), repeated nosebleeds, or persistent blocked nasal passages or sinuses, and frequent ear infections, make an appointment with your doctor as soon as possible, especially if you currently use, or have ever used, tobacco or alcohol.

The most effective ways to help prevent the development of squamous cell carcinoma of the head and neck are avoiding or quitting smoking, chewing tobacco, and snuff, avoiding excessive alcohol use, practicing good oral hygiene, visiting the dentist regularly, and avoiding oral infection with the human papilloma virus (HPV) by practicing safe oral sex.